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Indexing Non-merohedrally Twinned Crystals by Bruker'sAPEX2 and Agilent's CrysAlis^(PRO), an Example of a Crystal Structure That Can Be Refined through Either the PLATONRoute or the ‘HKLF 5' Route, and, Simultaneous Data Collection of Two Crystals in a Tw

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Chinese Journal of Structural Chemistry 2014年第2期33卷 294-303页

作者： ng seik weng Department of Chemistry University of Malaya 50603 Kuala Lumpur Malaysia Chemistry Department King Abdulaziz University

The first part of this report describes the data reduction of non-merohedrally twinned crystals measured on Bruker and Agilent area-detector diffractometers. The image frames of methyl-2-aminopyrazine-3-carboxylate were processed with APEX2 to furnish a set of overlapping diffraction indices that were used for solution and refinement. CrysAlisPRO was used for processing the frames of bis（diethyldicarbamato）nickel, which exists in monoclinic and tetragonal polymorphs, and in untwinned and twinned forms. In the second part, the crystal structure of [（3-formyl-4- hydroxyphenyl）methyl]triphenylphosphanium chloride was refined through the ‘HKLF 5＇（based on a combined set of diffraction indices） and PLATON（based on one set of diffraction indices） routes to give identical outcomes because the amount of overlap of the twin domains is small. For the third part, in a proof-of-concept investigation, the diffraction pattern of untwinned and twinned 4-{（E）-（4-aminophenyl）diazenyl]phenylamine was recorded simultaneously in one run; the three domains could be indexed and the crystal structure satisfactorily refined. The refinement was identical to those derived from independent measurements; the crystal structure features two independent centrosymmetric molecules, one of which is ordered and the other whole-molecule-disordered. This two-in-one run opens up the possibility that two or more crystals having different atomic compositions can be measured simultaneously if their reciprocal lattices do not overlap significantly.

关键词： merohedral non-merohedral twin APEX2 Crys Alis^PRO two-in-one data collection

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‘Whole-molecule Disorder’ Refinement of 4-Tricyanovinyl-N,N-diethylaniline

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Chinese Journal of Structural Chemistry 2011年第9期30卷 1286-1288页

作者： ng seik weng Department of Chemistry University of Malaya Chemistry Department Faculty of Science King Abdulaziz University

The molecule of 4-tricyanovinyl-N,N-diethylaniline is disordered about an axis that is close to the axis passing through the 1,4-carbon atoms. The disorder is a 1：1 type of disorder that involves only part of the molecule as the diethylamino substitutent and the three nitrogen atoms of the tricyanovinyl substituent are ordered. The treatment of the nearly ‘whole-molecule disorder’ by employing a small number of restraints is described. Crystal data： C15H14N4, triclinic, P , a = 7.1996（5）, b = 7.7232（5）, c = 12.4171（8） , α = 99.350（1）, β = 94.647（1）, γ = 103.312（1）o and V = 657.90（8） 3 at –173 K.

关键词： whole-molecule disorder

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‘Whole-molecule Disorder’ Refinement of 4-(4-Hydroxybenzylideneiminio)phenol Hemichloride Hemihydroxide

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Chinese Journal of Structural Chemistry 2011年第9期30卷 1283-1285页

作者： ng seik weng Department of Chemistry University of Malaya

The two independent cations of the salt, [HO-C6H4-CH=NH-C6H4-OH]·1/2OH·1/2Cl, are both disordered about an axis connecting the two oxygen atoms at the para-positions of the aromatic rings, the disorder being in a 83：17 ratio in one cation and 91：9 in the other. The hydroxide and chloride anions are ordered. The treatment of the nearly ‘whole-molecule disorder’ by employing a small number of restraints is described. Crystal data： C13H12.5Cl0.5NO2.5, triclinic, P , a = 9.1731（4）, b = 9.2048（4）, c = 15.9144（7） , α = 104.822（1）, β = 90.077（1）, γ = 118.641（1）o and V = 1127.86（9） 3 at –173 K.

关键词： whole-molecule disorder

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On Chiral Space Groups and Chiral Molecules

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Chinese Journal of Structural Chemistry 2003年第1期22卷 37-38页

作者： ng seik weng 胡盛志 Institute of Postgraduate Studies University of Malaya 50603 Kuala Lumpur Malaysia Department of Chemistry Xiamen University Xiamen 361005 China

This note explains the relationship (as well as the absence of a relationship) between chiral space groups and chiral molecules (which have absolute configurations). For a chiral molecule, which must crystallize in a chiral space group, the outcome of the absolute configuration determination must be linked to some other properties of the chiral crystal such as its optical activity for the observation to the relevant.

关键词：手性空间群手性分子手性化合物有机合成有机化合物晶体结构

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Non-merohedrally Twinned Crystal Structure of the Co-crystal Ethyl 6-(2-5-(Ethoxycarbonyl)-pyridin-2-yl-1,2-dihydroxyethyl)pyridine-3-carb-oxylateethyl 6-(2-5-(Ethoxycarbonyl)pyridin-2-yl-2-hydroxyacetyl)pyridine-3-carboxylate(0.69/0.31)

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Chinese Journal of Structural Chemistry 2013年第8期32卷 1159-1162页

作者： ZHAng Wen-Hua ng seik weng Institute of Materials Research & Engineering Department of Chemistry University of Malaya Chemistry Department King Abdulaziz University

The two component molecules of the co-crystal 0.69（C18H2ON206）.0.31（C18H18N2O6） lie on a center-of-inversion that exists midway along the ethylene chain connecting the two aromatic rings. The two molecules are superimposed. The crystal is also a non-morohedral twin with a minor 37.7（2）% component. The refinement of this twinned and disordered crystal structure is detailed. Crystal data： C18H19.38N2O6, monoclinic, P21/c, a = 17.1687（8）, b = 5.4389（2）, c = 9.3261（4） A, b = 95.270（5）° and V= 867.18（6） A3 at -173 ℃.

关键词： co-crystal non-merohedral twin

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Some Strategies for the Refinement of Disordered Structures with the SHELXL-97 Refinement Program

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Chinese Journal of Structural Chemistry 2005年第12期24卷 1425-1439页

作者： ng seik weng (Department of Chemistry, University of Malaya, Kuala Lumpur 50603, Malaysia) ng seik weng Department of Chemistry University of Malaya Kuala Lumpur 50603 Malaysia

Examples of the refinement of disordered structures taken from work published in Acta Crystallographica are presented together with explanations on how the disordered structures are dealt with. The constraint and restraint commands in the SHELXL-97 refinement program that are specific to the particular type of disorder are described. Some ways to divine the hydrogen atoms on water are given in detail. The refinements of the Flack parameters and twinned structures are briefly discussed.

关键词： disorder refinement restraints

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Crystal Structure of catena-[(Tetrakis-μ_2-acetato-μ_2-4,4'-bipyridine) dicopper(Ⅱ)] Acetonitrile Solvate

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Chinese Journal of Structural Chemistry 2007年第1期26卷 29-32页

作者：温一航何银华冯云龙 ng seik weng Zhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces Institute of Physical Chemistry Zhejiang Normal University Department of Chemistry University of MalayaKuala Lumpur 50603 Malaysia

The title compound, [Cu2（CH3COO）4（C8H10N2）]n·nCH3CN 1 （C8H10N2, 4,4＇-bipy = 4,4＇-bipyridine）, has been solvothermally synthesized in CH3CN and characterized by X-ray diffraction. The crystal is of monoclinic, space group Cc with α = 22.626（6）, b = 14.012（4）, c = 15.106（4） ]A, β = 107.610（3）°, V = 4565（2） ]A^3, C20H23Cu2N3O8, Mr = 560.49, Z = 8, Dc = 1.631 g/cm^3,μ = 1.914 mm^-1, Flack parameter = 0.48（1）, F（000） = 2288, R = 0.042 and wR = 0.098 for 8887 observed reflections （I 〉 20（I））. It consists of nearly linear one-dimensional chains [Cu2（CH3COO）4（C8H10N2）]n derived from paddle-wheel [Cu2（CH3COO）4] unit linked by 4,4＇-bipy, and CH3CN as guest molecule regularly decorates between the chains.

关键词： Cu complex paddle-wheel unit crystal strueture guest molecule

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GS型包合物G_2PEDS·MeOH·2(H_2O)和G_2PEDS·naphthalene的合成与晶体结构

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有机化学 2002年第11期22卷 889-893页

作者：廖成竹蔡继文冯小龙 ng seik weng 广州中山大学化学与化学工程学院广州510275 InstituteofPostgraduateStudies

合成了两个由胍盐 (G)和 4 ,4′ 苯醚二磺酸 (PEDS)为主体框架所形成的主 -客体包合物 ,分别为 [(CH6 N3) ]2[(C1 2 H8O7S2 ) ]·MeOH·2 (H2 O) (1)和 [(CH6 N3) ]2 [(C1 2 H8O7S2 ) ]·(C1 0 H8) (2 ) .两个化合物都是以P 1空间群结... 详细信息

合成了两个由胍盐 (G)和 4 ,4′ 苯醚二磺酸 (PEDS)为主体框架所形成的主 -客体包合物 ,分别为 [(CH6 N3) ]2[(C1 2 H8O7S2 ) ]·MeOH·2 (H2 O) (1)和 [(CH6 N3) ]2 [(C1 2 H8O7S2 ) ]·(C1 0 H8) (2 ) .两个化合物都是以P 1空间群结晶 ,晶胞参数分别为 :1a =0 75 0 9(4)nm ,b =1 2 113(6 )nm ,c =1 5 936 (8)nm ,α =10 2 6 36 (10 )°,β =10 2 70 3(11)° ,γ =91 318(10 )°;2a =0 75 4 0 9(3)nm ,b =1 2 15 84 (5 )nm ,c =3 0 9376 (14 )nm ,α =81 5 0 6 (2 )°,β =89 6 6 9(2 )°,γ =88 890 (2 )° .在这两个晶体结构中 ,G和PEDS通过氢键形成了双夹层 -双柱子的主体框架 ,客体分子被包合在平行于a轴方向的晶格空间 .这种双夹层 -双柱子的主体框架在由胍盐 (G)和有机二磺酸 (S)体系所形成的。

关键词：胍盐 4 4’-苯醚二磺酸主—客体化合物构筑异构体 GS型包合物 G2PEDS·MeOH·2(H2O) G2PEDS·naphthaEene 晶体结构

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Space Group of Aquaimidazolemaleatozinc, [(H_2O)(C_3H_4N_2)(O_2CCH=CHCO_2Zn)]_n

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Chinese Journal of Structural Chemistry 2005年第1期24卷 121-121页

作者： ng seik weng Department of Chemistry University of Malaya 50603 Kuala Lumpur Malaysia

The space group of [(H2O)(C3H4N2)(O2CCH=CHCO2Zn)]n, which was originally described in the acentric Pc space group (Liu et al., Chin. J. Struct. Chem. 2004, 23, 160～163), is re-described in the centric P21/c space g... 详细信息

关键词： CCH O2CCH=CHCO2Zn Space Group of Aquaimidazolemaleatozinc O2CCH C3H4N2 H2O

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On the Crystal Structure of [Cu(OH)_2(H_2O)_2(4-C_5H_4NCOOH)_2]

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Chinese Journal of Structural Chemistry 2003年第4期22卷 495-495页

作者： ng seik weng Department of Chemistry University of Malaya

The compound described as [Cu(OH)2(H2O)2(4-C5H4NCOOH)2] in Chin. J. Struct. Chem., 2001, 20: 478-480 is instead the compound [Cu(H2O)4(4-C5H4NCOO)2], whose crystal structure has already been published elsewhere.

关键词： C5H4NCOOH H2O Cu On the Crystal Structure of

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